It means the following (extract from this document [PDF] on EICTA website):


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4. Requirements for the label “HD ready”

A display device has to cover the following requirements to be awarded the label “HD ready”:

1. Display, display engine
   
   
   • The minimum native resolution of the display (e.g. LCD, PDP) or display
     engine (e.g. DLP) is 720 physical lines in wide aspect ratio.
   
   
   
2. Video Interfaces
   
   
   • The display device accepts HD input via:
     
     
     • Analogue YPbPr1, and
     • DVI or HDMI
     
     
   • HD capable inputs accept the following HD video formats:
     
     
     • 1280x720 @ 50 and 60Hz progressive (“720p”), and
     • 1920x1080 @ 50 and 60Hz interlaced (“1080i”)
     
     
   • The DVI or HDMI input supports content protection (HDCP)

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